Czochralski growth of Ge1 − xSix alloy crystals

Single crystal Ge1 − xSix alloys of composition 0 < x < 0.64 were grown by the Czochralski method. In particular, a single crystal 20 mm in diameter and 60 mm in length with variable composition 0.004 < x < 0.03 along the growth direction, and a crystal 12 mm in diameter and 20 mm in length with composition 0.21 < x < 0.25 were obtained. The crystals became Ge rich along the growth direction as determined by energy dispersive X-ray (EDX) spectroscopy. Fine striation structures in the crystals were observed by X-ray topography.